. >>> lance armstrong has now admitted he used performance- enhancing drugs during his cycling career. as juliette goodrich tells us, armstrong is also explaining how he internally justified his doping. >> yes or no, did you ever take banned substances to enhance your cycling performance? >> yes. >> yes or no, was one of those banned substances epo? >> yes. >> did you ever blood dope or use blood transfusions to enhance your cycling performance? >> yes. >> reporter: the 7-time tour de france winner now stripped of his titles and banned for life telling a much different story. the truth. >> i have used this situation as one big lie. >> reporter: after years of denials under oath. >> were you a bully? >> uhm.... yeah. yeah. i was a bully. >> reporter: armstrong said he didn't invent the doping and banned substance culture. but he didn't stop it, either. >> my, uhm, cocktail so to speak was -- was only, uhm, epo, but not a lot. transfusions and testosterone. which in a weird way i almost justified because of -- because of my history, obviously, with testicular cancer. >> reporter: was he